Server to cache protocol for improved web performance

摘要

On the Internet (106), rather than retrieving a frequently requested Web object from its originating server (105) in response to a request from a client terminal (101, 102), the object rather can be retrieved from a cache (103) within the Internet Access Service Provider (IASP) (104), which connects the client terminal to the Internet. What is stored in the cache may, however, not be the most recent version of the object. Distinct from providing the Web object itself, information about changes to the object is provided by the server in response to a cache request that is asynchronous to a request from a client for the object. Such information about changes to an object includes the date and time when the object was last modified, the byte size of the modified object, and information on the type of content of the object. After receiving this information about changes to an object, the cache may then request that a copy of the object be downloaded to it.